The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Nov. 25, 1997
Filed:
Oct. 27, 1994
Yoichi Takagi, Hitachi, JP;
Masayasu Kato, Hitachi, JP;
Takashi Miyakita, Tokyo, JP;
Katsuji Terazono, Tokyo, JP;
Shigeharu Jikan, Omiya, JP;
Takeo Tamezawa, Kawasaki, JP;
Toshiaki Hara, Otsu, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
A number of fish may be counted by emitting an ultrasonic wave or an electromagnetic wave toward a predetermined area of a body of water where fish pass (e.g., a fish farming pool, a river or the like). Reflected waves are received from the fish bodies so that the reflected waves received from a cross section of the predetermined area are periodically stored. An ultrasonic wave fish shade image is produced that shows changes of fish shades. Fish are counted by performing an image processing which discriminates the ultrasonic wave fish shade image based on a predetermined fish shade decision rule. This arrangement reduces errors occuring due to muddiness and dust in the water and allows an automatic continuous fish counting ability over a long time period.